Articles de revues sur le sujet « GIS, DTM, Geomorphometry »
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1
Šamanović, S., D. Medak et D. Gajski. « ANALYSIS OF THE PIT REMOVAL METHODS IN DIGITAL TERRAIN MODELS OF VARIOUS RESOLUTIONS ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B2 (7 juin 2016) : 235–39. http://dx.doi.org/10.5194/isprs-archives-xli-b2-235-2016.
Texte intégralRésumé :
Digital terrain model (DTM) is the base for calculation of the surface runoff under the influence of the gravity (gravity flow) in hydrological analysis. It is important to produce hydrologically corrected DTM with the removed natural and artificial depressions to avoid numerical problems in algorithms of the gravity flow. The pit removal procedure changes geomorphometry of the DTM. GIS software packages use pit removal algorithm independently of geomorphmetric features of the analyzed area. In need of minimally modified DTM after the pit removal areas, the carving method (deepen drainage routes) and the filling method (fill sink) were analyzed on three different geomorphometric areas (bare mountain range, hilly wooded area and the plain area intersected with the network of the drainage canals). The recommendation is given for the choice of geomorphometric least changing DTM algorithm. The input data are raster data of elevation points created by stereoscopic photogrammetry method in 5x5 and 25x25 meter resolution. Differences have been noticed during the process of creating raster data. The recommendation is given for the choice of the most acceptable method for each type of area on the basis of comparison of the original elevation points with the elevation points in created DTM.
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Šamanović, S., D. Medak et D. Gajski. « ANALYSIS OF THE PIT REMOVAL METHODS IN DIGITAL TERRAIN MODELS OF VARIOUS RESOLUTIONS ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B2 (7 juin 2016) : 235–39. http://dx.doi.org/10.5194/isprsarchives-xli-b2-235-2016.
Texte intégralRésumé :
Digital terrain model (DTM) is the base for calculation of the surface runoff under the influence of the gravity (gravity flow) in hydrological analysis. It is important to produce hydrologically corrected DTM with the removed natural and artificial depressions to avoid numerical problems in algorithms of the gravity flow. The pit removal procedure changes geomorphometry of the DTM. GIS software packages use pit removal algorithm independently of geomorphmetric features of the analyzed area. In need of minimally modified DTM after the pit removal areas, the carving method (deepen drainage routes) and the filling method (fill sink) were analyzed on three different geomorphometric areas (bare mountain range, hilly wooded area and the plain area intersected with the network of the drainage canals). The recommendation is given for the choice of geomorphometric least changing DTM algorithm. The input data are raster data of elevation points created by stereoscopic photogrammetry method in 5x5 and 25x25 meter resolution. Differences have been noticed during the process of creating raster data. The recommendation is given for the choice of the most acceptable method for each type of area on the basis of comparison of the original elevation points with the elevation points in created DTM.
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Stupin, Vladimir P., et Irina A. Karpova. « GIS ANALYSIS OF DEM IN THE INTERESTS OF SPECIALIZED MAPPING OF MINING TERRAIN ». Interexpo GEO-Siberia 1 (21 mai 2021) : 194–203. http://dx.doi.org/10.33764/2618-981x-2021-1-194-203.
Texte intégralRésumé :
Using the example of the Korshunovsky GOK quarry, the possibilities of processing publicly available SRTM C-SIR and ASTER GDEM DEM data and remote sensing materials obtained from LANDSAT and SENTINEL satellites in the SAGA GIS for specialized mapping of mountainous terrain are considered. The results of constructing derived geomorphometric maps based on DEM are presented. Restrictions on the use of the materials under consideration are justified.
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Pareta, Kuldeep, et Upasana Pareta. « Geomorphological Analysis and Hydrological Potential Zone of Baira River Watershed, Churah in Chamba District of Himachal Pradesh, India ». Indonesian Journal of Science and Technology 2, no 1 (1 avril 2017) : 26. http://dx.doi.org/10.17509/ijost.v2i1.5987.
Texte intégralRésumé :
In the present study, an attempt has been made to study the quantitative geomorphological analysis and hydrological characterization of 95 micro-watersheds (MWS) of Baira river watershed in Himachal Pradesh, India with an area of 425.25 Km2. First time in the world, total 173 morphometric parameters have been generated in a single watershed using satellite remote sensing data (i.e. IRS-P6 ResourceSAT-1 LISS-III, LandSAT-7 ETM+, and LandSAT-8 PAN & OLI merge data), digital elevation models (i.e. IRS-P5 CartoSAT-1 DEM, ASTER DEM data), and soI topographical maps of 1: 50,000 scale. The ninety-five micro-watersheds (MWS) of Baira river watershed have been prioritized through the morphometric analysis of different morphometric parameters (i.e. drainage network, basin geometry, drainage texture analysis, and relief characterizes ). The study has concurrently established the importance of geomorphometry as well as the utility of remote sensing and GIS technology for hydrological characterization of the watershed and there for better resource and environmental managements.
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Lemenkova, Polina. « Scripting methods in topographic data processing on the example of Ethiopia ». SINET : Ethiopian Journal of Science 44, no 1 (9 juin 2021) : 91–107. http://dx.doi.org/10.4314/sinet.v44i1.9.
Texte intégralRésumé :
This study evaluates the geomorphometric parameters of the topography in Ethiopia using scripting cartographic methods by applying R languages (packages 'tmap' and 'raster') and Generic Mapping Tools (gmt) for 2D and 3D topographic modelling. Data were collected from the open source repositories on geospatial data with high resolution: gebco with 15 arc-second and etopo1 with 1 arc-minute resolution and embedded dataset of srtm 90 m in 'raster' library of R. The study demonstrated application of the programming approaches in cartographic data visualization and mapping for geomorphometric analysis. This included modelling of slope steepness, aspect and hillshade visualized using dem srtm90 to derive geomorphometric parameters of slope, aspect and hillshade of Ethiopia and demonstrate contrasting topography and variability climate setting of Ethiopia. The topography of the country is mapped, including Great Rift Valley, Afar Depression, Ogaden Desert and the most distinctive features of the Ethiopian Highlands. A variety of topographical zones is demonstrated on the presented maps. The results include 6 new maps made using programming console-based approach which is a novel method of cartographic visualization compared to traditional gis software. The most important fragments of the codes are presented and technical explanations are provided. The presented series of 6 new maps contributes to the cartographic data on Ethiopia and presents the methodology of scripting mapping techniques.
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Capoane, Viviane. « Implicações da resolução e fonte de modelos altimétricos na análise quantitativa de atributos geomorfométricos para bacia hidrográfica do córrego Guariroba, Campo Grande, MS ». Revista Brasileira de Geografia Física 13, no 5 (29 juillet 2020) : 2417. http://dx.doi.org/10.26848/rbgf.v13.5.p2417-2432.
Texte intégralRésumé :
O relevo é um dos principais fatores que controlam os processos que ocorrem na superfície terrestre. Dessa forma, a caracterização geomorfométrica é um elemento básico para o planejamento e gestão de bacias hidrográficas. Considerando que a resolução da grade do modelo altimétrico influencia as características topográficas extraídas, este trabalho teve como objetivo quantificar atributos geomorfométricos para a bacia hidrográfica do córrego Guariroba a partir de Modelos Digitais de Superfície (MDSs) baseados em imagens de radar – SRTM e Alos Palsar – e Modelo Digital de Elevação (MDE) gerado por aerofotogrametria, com tamanhos de grade de 30, 12,5 e 5 m, respectivamente, visando demonstrar o efeito da resolução espacial da grade nos parâmetros derivados, bem como subsidiar a escolha do modelo altimétrico apropriado para orientar o planejamento e o gerenciamento dos recursos solo e água nesta bacia hidrográfica. Os parâmetros geomorfométricos foram avaliados sob três perspectivas: rede de drenagem, geometria e características de relevo. A rede de drenagem é do tipo dendrítica; a hierarquia fluvial é de quinta ordem; a forma da bacia é menos alongada; o canal principal tende a ser retilíneo com alta influência da carga sedimentar; e a área possui baixo relevo e declives e é dissecada moderadamente. As bases de menor resolução espacial (MDS 30 e 12,5m) subestimaram as áreas planas (27,0 e 16,1%) e com relevo suave ondulado (4,4 e 29,2%); e superestimaram a área com relevo ondulado (34,9 e 70,9%) e com declive superior a 5% (29,3 e 77,0%), respectivamente. O modelo altimétrico que permitiu melhor delineamento dos parâmetros geomorfométricos foi o gerado a partir do levantamento aerofotogramétrico. Implications of the resolution and source of altimetric models in the quantitative analysis of geomorphometric attributes for the Guariroba watershed, Campo Grande, MS A B S T R A C TRelief is one of the main factors that control the processes that occur on the Earth's surface. Thus, geomorphometric characterization is a basic element for the planning and management of watersheds. The objective of this study was to investigate the impact of Digital Surface Models (DSMs) and Digital Elevation Model (DEM) resolution on the extraction and quantification of geomorphometric attributes for the Guariroba watershed. Elevation data base generated by radar (Alos Palsar and SRTM) and photogrammetry techniques with 30, 12.5 and 5m grid size, were used. The geomorphometric attributes were evaluated from three perspectives: drainage network, geometry, and relief characteristics. The drainage network is of the dendritic type; the river hierarchy, of fifth order; the shape of the basin, less elongated; the main channel, rectilinear with high influence of sedimentary load; and the area, dissected moderately with low relief and slopes. The grids with the lowest spatial resolution (DSM 30 and 12.5m) underestimated the flat areas (27.0 and 16.1%) and those with soft wavy relief (4.4 and 29.2%); and overestimated the areas with wavy relief (34.9 and 70.9%) and those with a slope of more than 5% (29.3 and 77.0%), respectively. The altimetric model which allowed a better determination of the geomorphometric attributes was generated from the aerophotogrammetric survey. The results constitute a baseline database to aid in planning and management of soil and water resources in this watershed.Keywords: Grid size, GIS, Soil and water conservation, Environmental planning.
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Loye, A., M. Jaboyedoff et A. Pedrazzini. « Identification of potential rockfall source areas at a regional scale using a DEM-based geomorphometric analysis ». Natural Hazards and Earth System Sciences 9, no 5 (8 octobre 2009) : 1643–53. http://dx.doi.org/10.5194/nhess-9-1643-2009.
Texte intégralRésumé :
Abstract. The availability of high resolution Digital Elevation Models (DEM) at a regional scale enables the analysis of topography with high levels of detail. Hence, a DEM-based geomorphometric approach becomes more accurate for detecting potential rockfall sources. Potential rockfall source areas are identified according to the slope angle distribution deduced from high resolution DEM crossed with other information extracted from geological and topographic maps in GIS format. The slope angle distribution can be decomposed in several Gaussian distributions that can be considered as characteristic of morphological units: rock cliffs, steep slopes, footslopes and plains. A terrain is considered as potential rockfall sources when their slope angles lie over an angle threshold, which is defined where the Gaussian distribution of the morphological unit "Rock cliffs" become dominant over the one of "Steep slopes". In addition to this analysis, the cliff outcrops indicated by the topographic maps were added. They contain however "flat areas", so that only the slope angles values above the mode of the Gaussian distribution of the morphological unit "Steep slopes" were considered. An application of this method is presented over the entire Canton of Vaud (3200 km2), Switzerland. The results were compared with rockfall sources observed on the field and orthophotos analysis in order to validate the method. Finally, the influence of the cell size of the DEM is inspected by applying the methodology over six different DEM resolutions.
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Mousavi, S. R., F. Sarmadian, A. Rahmani et S. E. Khamoshi. « DIGITAL SOIL MAPPING WITH REGRESSION TREE CLASSIFICATION APPROACHES BY RS AND GEOMORPHOMETRY COVARIATE IN THE QAZVIN PLAIN, IRAN ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-4/W18 (18 octobre 2019) : 773–77. http://dx.doi.org/10.5194/isprs-archives-xlii-4-w18-773-2019.
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Abstract. Digital soil mapping applies soil attributes, Remote sensing and Geomorphometrics indices to estimate soil types and properties at unobserved locations. This study carried out in order to comparison two data mining algorithms such as Random Forest (RF) and Boosting Regression tree (BRT) and two features selection principal component analysis (PCA) and variance inflation factor (VIF) for predicting soil taxonomy class at great group and subgroup levels. A total of 61 soil profile observation based on stratified random determined and digged in area with approximately 16660 hectares.19 RS indices and geomorphometrics covariates derivated from Landsate-8 imagery and DEM with 30 meters’ resolution in ERDAS IMAGINE 2014 and SAGA GIS version 7.0 software’s. Also to run four Data mining algorithms scenarios (PCA-RF, VIF-RF, PCA-BRT, VIF-BRT) from “Randomforest” and “C.5” packages were used in R studio software. 80% and 20% from soil profiles were applied for calibrating and validating. The results showed that in PCA and VIF approaches, eight covariates such as (Relative slope position, diffuse insolation, modified catchment, normalized height, RVI, Standard height, TWI, Valley depth) and six covariates (NDVI, DVI, Catchment area, DEM, Salinity index, Standard height) were selected. The validation results based on overall accuracy and kappa index for scenarios at great group level indicated that 88,93,62, 54 and 75,83,51,45 percentages and for subgroup level had 70, 77, 54, 47 and 60, 71, 43, 37 percentages, respectively. Generally, VIF-RF had accuracy rather than from other scenarios at two categorical level in this study area.
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Rahmati, Omid, Zahra Kalantari, Mahmood Samadi, Evelyn Uuemaai, Davoud Davoudi Moghaddam, Omid Asadi Nalivan, Georgia Destouni et Dieu Tien Bui. « GIS-Based Site Selection for Check Dams in Watersheds : Considering Geomorphometric and Topo-Hydrological Factors ». Sustainability 11, no 20 (13 octobre 2019) : 5639. http://dx.doi.org/10.3390/su11205639.
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Check dams are widely used watershed management measures for reducing flood peak discharge and sediment transport, and increasing lag time and groundwater recharge throughout the world. However, identifying the best suitable sites for check dams within the stream networks of various watersheds remains challenging. This study aimed to develop an open-source software with user-friendly interface for screening the stream network possibilities and identifying and guiding the selection of suitable sites for check dams within watersheds. In this developed site selection software (SSS), multi-criteria decision analysis (MCDA) was integrated into geographic information systems (GIS), which allowed for numerous spatial data of the multiple criteria to be relatively simply and visually processed. Different geomorphometric and topo-hydrological factors were considered and accounted for to enhance the SSS identification of the best locations for check dams. The factors included topographic wetness index (TWI), terrain ruggedness index (TRI), topographic position index (TPI), sediment transport index (STI), stream power index (SPI), slope, drainage density (DD), and stream order (SO). The site identification performance of the SSS was assessed using the receiver operating characteristic (ROC) curve method, with results for the case study example of the Poldokhtar watershed in Iran showing excellent performance and identifying 327 potential sites for efficient check dam construction in this watershed. The SSS tool is not site-specific but is rather general, adaptive, and comprehensive, such that it can and should be further applied and tested across different watersheds and parts of the world.
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Bezgodova, O. V. « Structural and Morphometric Analysis of the Ihe-Ukhgun Small River Basin (Irkut River Basin) ». Bulletin of Irkutsk State University. Series Earth Sciences 37 (2021) : 3–16. http://dx.doi.org/10.26516/2073-3402.2021.37.3.
Texte intégralRésumé :
The article is devoted to the structural and morphometric analysis of a small rivers using the example of the Ihe-Ukhgun river basin (left tributary of the Irkut river), which is based on a complex processing of a digital elevation model (DEM). The author has prepared a hydrologically correct DEM based on the ALOS Digital Surface Model (DSM) satellite data, carried out an automated calculation and mapping of the basin erosion network based on the DEM data, calculated the structural indicators of the third-order basins for analyzing the basin organization of the small rivers network. Structural and morphometric analysis using GIS was practically not used for the Ihe-Ukhgun river basin which is placed in different landscapes, geological and geomorphological conditions. The work is based on geomorphometric and structural morphometric methods as well as the method of geoinformation mapping and relief modeling for analyzing lower-order basins. Thalweg erosion network modeling up to the fourth order of the river basin Ihe-Uhgun was carried out with using of DEM analysis in the ArcGIS 10 program. The map of the erosional network of the basin was constructed, morphometric indicators of rivers (length, area of basins, sum of slopes, coefficient of basin asymmetry, etc.) were obtained, and then the indices of the basin structure (structure of bifurcation, lengths, areas and slopes) were calculated. As a result, an asymmetric erosion network was revealed, which indicates a great work in the transfer of matter of first-order streams. First-order streams exceed those of the second and third orders streams in terms of catchment area, length and steepness of adjacent slopes. The interrelation of morphometric characteristics of different-order streams within third order sub-basins are most fully traced with the using of structural indices and their comparison with modal indicators. In general, the Ihe-Ukhgun river basin is characterized by a heterogeneous structure of the streams ratio of the first, second and third orders. The basins of the Khurguta, Khubyty and Ulan-Gol rivers have the highest degree of homogeneity. At the same time, for the Ihe-Ukhgun river basin, there is no direct relationship with the area of the third order drainage basins.
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Lemenkova, Polina. « Gobi Altai, Khangai and Khentii Mountains mapped by a mixed-method cartographic approach for comparative geophysical analysis ». Mongolian Geoscientist 26, no 52 (23 juin 2021) : 62–79. http://dx.doi.org/10.5564/mgs.v26i52.1512.
Texte intégralRésumé :
Geologic and geophysical mapping has been so far limited to the traditional single-method GIS-based mapping. A new approach combining integrated analysis of data on geology, gravity, topography and geomorphology is presented for regional characterization of the geophysical setting in Mongolia: the Gobi Altai Mountains, the Khangai Mountains and Khentii Mountains with surrounding areas. Nine new maps have been produced from the high-resolution datasets: GEBCO, gravity raster, USGS geological data and SRTM-90 DEM geomorphological grid. Methodology includes three tools for cartographic data visualization: i) Generic Mapping Tools (GMT), ii) R programming language (‘raster’ and ‘tmap’ libraries); iii) QGIS. The results demonstrated strong agreement between the estimated values in gravity and topography grids, distribution of geological units and provinces over the country and geomorphological landforms with respect to the mountain ranges: Altai, Khangai and Khentii Mountains. The highest values in the gravity anomalies correspond to the mountain ranges in the Altai Mountains and Khangai Mountains (<80 mGal); high values correspond to the Khentii Mountains (20–60 mGal). Contrariwise, the basins of the Uvs Nuur and Khyargas Nuur show negative values (<-80 mGal). The NE- to NNE-oriented faulting and rift basins are clearly visible in the geophysical grids and geologic maps. The geomorphometric analysis performed based on the SRTM-90 DEM using R scripting demonstrated (1) slope, (2) aspect, (3) hillshade and (4) elevation models of Mongolia supported by histograms of data distribution and frequency. The study contributed to the cartographic methods and regional geological studies of Mongolia.
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Prasannakumar, V., H. Vijith et N. Geetha. « Terrain evaluation through the assessment of geomorphometric parameters using DEM and GIS : case study of two major sub-watersheds in Attapady, South India ». Arabian Journal of Geosciences 6, no 4 (2 octobre 2011) : 1141–51. http://dx.doi.org/10.1007/s12517-011-0408-2.
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Lemenkova, Polina. « A Script-Driven Approach to Mapping Satellite-Derived Topography and Gravity Data Over the Zagros Fold-and-Thrust Belt, Iran ». Artificial Satellites 57, no 2 (1 juin 2022) : 110–37. http://dx.doi.org/10.2478/arsa-2022-0006.
Texte intégralRésumé :
Abstract Integrated geophysical mapping benefits from visualizing multi-source datasets including gravity and satellite altimetry data using 2D and 3D techniques. Applying scripting cartographic approach by R language and GMT supported by traditional mapping in QGIS is presented in this paper with a case study of Iranian geomorphology and a special focus on Zagros Fold-and-Thrust Belt, a unique landform of the country affected by complex geodynamic structure. Several modules of GMT and ’tmap’ and ’raster’ packages of R language were shown to illustrate the efficiency of the console-based mapping by scripts. Data sources included high-resolution raster grids of GEBCO/SRTM, EGM-2008, SRTM DEM and vector geologic layers of USGS. The cartographic objective was to visualize thematic maps of Iran: topography, geology, satellite-derived gravity anomalies, geoid undulations and geomorphology. Various cartographic techniques were applied to plot the geophysical and topographic field gradients and categorical variations in geological structures and relief along the Zagros Fold-and-Thrust Belt. The structures of Elburz, Zagros, Kopet Dag and Makran slopes, Dasht-e Kavir, Dasht-e Lut and Great Salt Desert were visualized using 3D-and 2D techniques. The geomorphometric properties (slope, aspect, hillshade, elevations) were modelled by R. The study presented a series of 11 new maps made using a combination of scripting techniques and GIS for comparative geological-geophysical analysis. Listings of R and GMT scripting are provided for repeatability.
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Trofimetz, Lyubov, Evgeny Panidi, Natalia Chaadaeva, Elena Sankova, Taras Ivaneha, Angela Tyapkina, Anna Saraeva et al. « Application of the radiocesium method and morphometric relief indicators to the calculation of soil loss intensity on plowed slopes in the Sukhaya Orlitsa river basin ». InterCarto. InterGIS 27, no 4 (2021) : 135–49. http://dx.doi.org/10.35595/2414-9179-2021-4-27-135-149.
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Based on the authors’ data, the paper describes a methodology for assessing the spatial distribution of soil losses on the plowed slopes of the experimental site. The site is located in the basin of the Sukhaya Orlitsa River in the Orel District, Orel Region. The introduction of the principles of precision farming into land use practice requires a point estimate of soil losses, which is possible when using morphometric relief indicators. Geomorphometry methods in combination with GIS and the radiocaesium method made it possible to develop a method for calculating the specific activity of cesium-137 (as an indicator of soil losses) based on the morphometric parameters of the relief. The article presents the dependencies developed for depressions with a catchment area of ≤ 23,000 m2 and ≤ 50,000 m2. The development of a method for calculating soil losses in the elements of a depression complex on a plowed slope was carried out in two stages. At the first (field) stage, soil samples in the arable layer were taken in thalweg of depressions of different sizes. Sampling points were recorded during GPS survey. Gamma-spectrometric analysis of soil samples and their application to a digital elevation model (DEM) allowed to obtain a spatially distributed model of the specific activity of cesium-137 of Chernobyl origin on a scale of 1:10,000. To recognize the depressions, ultra-high resolution satellite images published in Google Earth were used. On the basis of the DEM, using the SAGA GIS tools, the authors built the fields of the collection area (calculated by the DEMON algorithm) and the profile curvature of the relief. The method was based on a system of dependences of the specific activity of cesium-137 on the collection area and the sign of the profile curvature. The specific activity of cesium-137 for inter-depression spaces was calculated using the equations developed for depressions with a collection area of up to 23,000 m2. To calculate soil losses, it was proposed to establish the reference value of cesium-137 individually for each of the three studied fields, which is due to the presence of the trend of Chernobyl fallout. In conditions of a polygonal block microrelief of paleocryogenic origin (which is widespread in the analyzed territory), the authors recommended determining the reference value of the specific activity of cesium-137 within block increases on the watershed surface of the plowed slopes. The trend was established on the results of the analysis of the layer-by-layer distribution of cesium-137 in depth in the thalweg of the depressions and in the balka, “receiving” overburdens from the fields under the study. Taking into account the results of the calculations, a map of the intensity of soil losses was constructed for the experimental site as of from 1986 to 2016.
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Nwilo, Peter C., Caleb O. Ogbeta, Olagoke E. Daramola, Chukwuma J. Okolie et Michael J. Orji. « Soil Erosion Susceptibility Mapping of Imo River Basin Using Modified Geomorphometric Prioritisation Method ». Quaestiones Geographicae, 26 septembre 2021. http://dx.doi.org/10.2478/quageo-2021-0029.
Texte intégralRésumé :
Abstract Gullies and other forms of erosion have been the greatest environmental problem and catastrophe in most high- and low-income countries. The challenge posed by soil erosion has compromised agricultural productivity, environmental biodiversity and food safety for the world's population. It is important to identify vulnerable areas to soil erosion in each region to initiate remedial measures. This study demonstrates the use of watershed morphometry coupled with weighted sum analysis (WSA) to estimate the soil erosion susceptibility of the Imo River Basin sub-watersheds (SWs) in South-Eastern Nigeria using satellite remote-sensing data and geographic information system (GIS) analysis. To this end, Shuttle Radar Topography Mission (SRTM), a Digital Elevation Model (DEM) with 30 m spatial resolution was used to extract and analyse 18 morphometric parameters including basic, linear, shape and relief. The method of receiver operating characteristics (ROC) curves was used to validate the model's prediction accuracy. This morphometry-based analysis resulted in the SWs being classified into zones of low, medium, high and very high erosion susceptibility. With regard to erosion susceptibility, 41.51% of the basin (2494.68 km2) is in the very high priority zone; while 10.50%, 44.33% and 3.66% of the basin are in the high, medium and low priority zones respectively. Validation of the final erosion susceptibility map showed a prediction accuracy of 81%. The use of satellite imagery and morphometric analysis in this study was cost- and time-effective for identifying areas susceptible to soil erosion.